The present invention relates generally to a floor treating apparatus, and more particularly to a solenoid valve and timing module to control the liquid supply system in a floor treating apparatus.
In a floor treating apparatus such as a floor scrubber, liquid from a liquid supply reservoir is supplied to a floor treating device such as a brush or a pad. The rate or amount of liquid supplied to the floor treating device is manually controlled by a choke cable and a conventional metering valve or ball valve. In order to control the amount of liquid supplied to the floor treating device, an operator must manually adjust the ball or needle valve until the desired amount of liquid supplied is achieved. It is difficult to accurately adjust the amount of liquid supplied because, as is known in the art, the design of a ball valve does not allow a linear increase or decrease in the amount of liquid that passes through the ball valve. Further, the operator must continuously open and close the ball valve to adjust the supply to avoid providing too little or too much liquid to the floor treating device. This manual operation sometimes causes undesirable liquid flow levels due to the inaccurate method of adjusting the ball valve to create the desired flow.
In addition to the inaccurate adjustment and delivery of liquid flow, the use of a ball valve in a floor treating apparatus has other drawbacks. The ball valve is normally located in the liquid flow line a few feet from the floor treating device. This causes a lag time when starting the liquid flow since the liquid must travel a few feet from the ball valve to the floor treating device when the ball valve is first opened. The location of the ball valve also causes a lag time when stopping the liquid flow since the liquid in the flow line between the ball valve and the floor treating device will continue to flow once the ball valve is closed. Another drawback to a ball valve or other conventional metering valves is that it is not always completely open when liquid is supplied. Therefore, particles tend to become trapped between the needle and seat or ball and seat thereby affecting the flow of liquid.